Re: [PATCH] i2c: atr: use kzalloc_flex

["Luca Ceresoli" <luca.ceresoli@bootlin.com>]

Hello Rosen,

On Fri Mar 13, 2026 at 1:23 AM CET, Rosen Penev wrote:
> Convert kzalloc_obj + kcalloc to kzalloc_flex to save an allocation.
>
> Add __counted_by to get extra runtime analysis. Move counting variable
> assignment immediately after allocation as required by __counted_by.

Not sure what you mean by the last sentence, you are not moving the
assignment.

> --- a/drivers/i2c/i2c-atr.c
> +++ b/drivers/i2c/i2c-atr.c
> @@ -58,8 +58,8 @@ struct i2c_atr_alias_pool {
>
>  	/* Protects aliases and use_mask */
>  	spinlock_t lock;
> -	u16 *aliases;
>  	unsigned long *use_mask;
> +	u16 aliases[] __counted_by(size);

Please reorder the parameters accordingly in the kdoc documentation above.

> @@ -137,22 +137,16 @@ static struct i2c_atr_alias_pool *i2c_atr_alloc_alias_pool(size_t num_aliases, b
>  	struct i2c_atr_alias_pool *alias_pool;
>  	int ret;
>
> -	alias_pool = kzalloc_obj(*alias_pool);
> +	alias_pool = kzalloc_flex(*alias_pool, aliases, num_aliases);
>  	if (!alias_pool)
>  		return ERR_PTR(-ENOMEM);
>
>  	alias_pool->size = num_aliases;

I'm not really sure about that, but I suspect kzalloc_flex() does set the
counter variable automatically if it's annotated using __counted_by. If
that's true, you can drop this line.

Otherwise LGTM.

Luca

--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com